Lupin – dream ingredient or allergy nightmare?
I have to say right up front, lupin looks promising but the jury is still out. Here’s the story so far. Research from Western Australia published in the American Journal of Clinical Nutrition found that a bread with 40% added lupin kernel flour lowered both systolic and diastolic blood pressure in 74 overweight men and women over 16 weeks. Compared to a standard white bread, the lupin-enriched bread dropped blood pressure by 3.0 and 0.6mm Hg respectively while their pulse pressure also decreased.
In a 2006 American Journal of Clinical Nutrition study, researchers reported that eating lupin flour-enriched bread at breakfast resulted in higher ‘feel full’ (satiety) scores and a lower overall food intake (488 kJ less) at lunch than eating white bread.
It makes sense. Both protein and fibre are things dieters already utilise to help them keep hunger pangs away. It significantly reduces total food intake and surprisingly cuts down on their intake at the following meal.
What is it? Lupin (Lupinus angustifolius) is a legume (bean), high in protein (over 40%) and fibre (around 30%), most of which is the soluble type. It’s also low in fat, which is mainly polyunsaturated with some omega-3, so it most closely resembles soy beans. In fact it’s been ear marked as the next major competitor to soy beans as a high protein ingredient in vegan sausages, noodles, breads, muffins or breakfast cereal.
The fat also is rich in lecithin, which is good for the heart. It contains natural antioxidants such as carotenoids (which account for its golden-yellow colour) and tocopherols which are converted into vitamin E.
What can it do for you? Eating foods contain lupin flour can help cut your food intake without going hungry thanks to the fibre and protein content. It is an excellent alternative to both wheat flour and soy products. It has a higher lysine content than cereals and is rich in the amino acid arginine which is a precursor of nitric oxide, a vasodilator in blood vessels. Like other legumes, it is gluten free and its starch is slowly digested, so as an ingredient it would help lower the GI of a food such as bread.
Lupin allergy is the downside. Major food manufacturers, however, are holding back from using lupin flour due to the likelihood of it provoking a severe allergic reaction like peanut (botanically a legume). It appears that people with peanut sensitivity may have cross-reactivity with lupin or the allergy may arise for no known reason.
Currently, food producers are not required to label lupin as a potential allergen unlike gluten or soy. Even though it’s not widely available, already two reports – in the Medical Journal of Australia and a case report in The Lancet (April 2005; no abstract) – describe four cases of anaphylaxis that can be traced back to hidden lupin. Immunologists suggest that allergic patients be tested for lupin sensitivity before eating it.
Where do you get it? At present, not many lupin-based products exist. In Australia, Bodhi’s Slimmers Choice bread is made with 40% lupin kernel flour. This was the bread used in both studies but it’s only available in Western Australia and some outlets in South Australia and Victoria. Website: www.bodhi.com.au.
‘Feel great – lose weight’ is the claim on the Lupin8 label. You add this yellow powder (made from a blend of lupin kernel flour, corn flour maize, oat bran, rice meal and psyllium husks) to food or cooking to reduce hunger pangs. It says it has a low GI on the label, but I haven’t seen any published test results, and there’s only 3 g carbs in a 9 g serving (about a tablespoon). You can buy it from pharmacies and health food shops in Australia and the manufacturer says it will be available in NZ and USA from March/April. Website: www.lupin8.com.au.
Want more information? The WA Department of Agriculture has a really excellent PDF on lupins generally and lupin research and background; and you can find out more about lupin flour at www.lupinflour.com.au.
Catherine Saxelby is an accredited dietitian and nutritionist and runs the Foodwatch Nutrition Centre. For more information onlupin and healthy eating, visit www.foodwatch.com.au.